CYCLOTRON RESONANCE PUMPING OF GAS LASERS.
Triannual rept. no. 2, 1 Oct 66-31 Jan 67,
RADIO CORP OF AMERICA PRINCETON NJ ASTRO ELECTRONICS APPLIED RESEARCH LAB
Pagination or Media Count:
Cw experiments were performed on argon lasers with dc and dcmicrowave excitation to study the effect of microwave electron-cyclotron-resonance pumping on laser discharges and laser output. The 4-mm laser tube, inside a microwave cavity on the magnet solenoid axis, was cooled by a fluorocarbon fluid. Resonance curves were obtained by varying the axial magnetic field, the microwave input being at fixed frequency 2.45 GHz. To discriminate between resonance effects and magnetic field effects, comparison was made between laser output curves for dcmicrowave excitation and for dc excitation. A sharp resonant B 890 G increase in laser output occurred at each pressure tested the distortion of the wings of the resonance curve was seen to be mainly due to magnetic effects on the dc discharge. The laser output approx. 10 mW at resonance with approx. 1200-W dc300-W microwaves was higher than that with approx. 1250-W dc by factors of 2, 2.3, and 3.0 at 0.33, 0.12, and 0.06 Torr, respectively. From these results it may resonably be deduced that the cyclotron resonance condition has a beneficial effect on electron energy distribution and laser output. However, for approximately equal total input powers no increase in laser output was obtained with the microwave cyclotron resonance discharge. In work on azimuthal ring discharge excitation at approximately 20 MHz, discharge power densities in excess of those required for laser operation were obtained in tubes more than 40 cm long. Author
- Lasers and Masers
- Nuclear Physics and Elementary Particle Physics